Atrial fibrillation (AF) is the most common sustained abnormal rhythm of the heart, affects an estimated 2.5 to 5 million individuals in the US, and can lead to stroke, heart failure, and premature death. For those with AF and other stroke risk factors, chronic anticoagulation is recommended to prevent intracardiac thrombus formation and stroke even if the AF is infrequent or short-lived. This standard of care is based partly on our inability to rapidly recognize and respond to AF recurrences which can often be brief and asymptomatic, but exposes the patient to the risk of anticoagulant-induced hemorrhage even during prolonged periods of sinus rhythm where the risk of stroke is presumably low. Recent advances in device technology and drug therapy, however, have the potential to change the way we manage AF. The use of a small leadless subcutaneous implantable cardiac monitor with remote data transmission capabilities (Reveal XT, Medtronic Inc.) provides the ability to remotely and continuously evaluate a patient for AF recurrences, even episodes that are brief and asymptomatic. In addition, the release of a unique oral thrombin inhibitor approved for use in non-valvular AF (Dabigatran [Pradaxa], Boehringer Ingelheim Inc.) allows for rapid onset anticoagulation within minutes to hours of a single oral dose. Together, these advances allow for continuous AF monitoring with targeted anticoagulation only around the time of an AF episode, thereby reducing the risk of drug-induced hemorrhage while still protecting against stroke. The aim of this pilot study is to assess the feasibility of intermittent anticoagulation wih dabigatran guided by continuous AF monitoring with Reveal XT and remote data transmission to a healthcare provider. The study will enroll 75 AF patients from three centers with 1 or 2 other risk factors for stroke who have demonstrated persistent sinus rhythm following a rhythm control intervention which may include medications, ablation, or surgery. This pilot study will provide logistical insights, demonstrate feasibility, and generate required data for sample-size estimates for an anticipated large scale clinical trial comparing chronic anticoagulation with Reveal XT-guided intermittent anticoagulation with dabigatran. This treatment modality can be anticipated to substantially reduce the exposure time to anticoagulation therapy, thereby reducing the risk of hemorrhage without increasing the risk of stroke. From a public health perspective, such a paradigm shift would reduce the cost of long-term anticoagulation, the impact of anticoagulant-related hemorrhage including the devastating consequences of intracranial hemorrhage, and improve quality of life in a portion of the millions of patients who already have AF and the 16 million expected to have the disease by the year 2050. If proven superior to current treatment methods this approach may improve a critical aspect of AF management and pave the way, along with advances in technology, for patient- directed in-home monitoring and treatment. PUBLIC HEALTH RELEVANCE: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with stroke, heart failure, premature death and significant cost to the healthcare system. Chronic anticoagulation, with its attendant risks of hemorrhage, is recommended for stroke prevention in patients with AF who also have other stroke risk factors, but may in fact only be necessary in the weeks surrounding an AF episode. This pilot study will assess the feasibility of treating patients with intermittent anticoagulation by using a new, rapid-onset oral thrombin inhibitor guided by an AF-sensing subcutaneous leadless implantable cardiac monitor with remote data transmission capabilities. If supported by a subsequent pivotal clinical trial, this paradigm shift could allow for reduced anticoagulation use, reduced hemorrhage risk, reduced cost and an improved quality of life with no increased risk of stroke in the ever-increasing AF population. (End of Abstract)